1. Field of the Invention
The present invention relates to a semiconductor chip to be electrically connected to a solid device and a semiconductor device using the same, and a method of fabricating the semiconductor chip.
2. Description of Related Art
In a case where a semiconductor chip is mounted on a printed wiring board by flip-chip 15 bonding or a case where semiconductor chips are joined to each other by overlapping one of the semiconductor chips with the other semiconductor chip to construct a semiconductor device having a chip-on-chip structure, a face-down mounting system or a face-up mounting system is applicable, for example. The face-down system is a mounting system in which the surface of a semiconductor chip is opposed to the surface of a printed wiring board or another semiconductor chip. Contrary to this, the face-up system is a mounting system in which the reverse surface of a semiconductor chip is opposed to the surface of a printed wiring board or another semiconductor chip. The surface of the semiconductor chip is a surface on the side of an active surface layer region where a functional device is formed on a semiconductor substrate forming a base body, and a surface opposite thereto is the reverse surface.
In a case where the face-down system is used, a metal electrode portion called a bump is formed in a raised state on the surface of the semiconductor chip. The bump is joined to a connecting pad formed on the surface of the printed wiring board or the other semiconductor chip.
In a case where the face-up system is used, a connecting pad on the surface of the semiconductor chip and a connecting pad on the surface of the printed wiring board or the other semiconductor chip are connected to each other by wire bonding.
In the case where the face-down system is used, the surface of the semiconductor chip is opposite to the printed wiring board or the other semiconductor chip as a base chip. Accordingly, it is impossible to take a structure in which three or more semiconductor chips are stacked by further joining to the semiconductor chip another semiconductor chip. Therefore, there is a limit to an improvement in an integration degree.
In the case where the face-up system is used, in the printed wiring board or the base semiconductor chip, a connecting pad must be provided outside the region where the semiconductor chip is stacked and joined thereto, for convenience of wire bonding. Therefore, the overall occupied area is considerably large, thereby preventing the integration degree from being improved.